Bedbugs are wingless, rust-colored insects that are roughly the size of an apple seed. They don't spread disease, but they do bite. Their bites can trigger allergic reactions, including welts and itching.

Recent media reports about bedbug epidemics have helped boost an industry filled with products and services that are designed to prevent bedbug infestations and/or get rid of these creatures if you already have them.

Now new research in the Journal of Economic Entomology shows that devices that produce sound waves do little to deter these creepy, crawly pests.

Researchers from Flagstaff, Ariz., purchased four ultrasonic devices online on Amazon.com and followed the instructions for use on their labels. During the experiment, they created an area where the device emitted sound waves, as well a silent comparison area.

There were no differences in the number of bedbugs observed in either area, suggesting that bedbugs were neither deterred by nor attracted to sound waves emitted by any of the devices.

As far back as 2001, the Federal Trade Commission sent warning letters to more than 60 manufacturers of these types of devices, saying that claims of effectiveness for these products must be supported by scientific evidence.

Ultrasonic Devices Don't Repel Bedbugs

Many in the insect-control field are not surprised by these findings.

"Throughout the annals of pest control, ultrasonic devices have been evaluated against everything from rodents to roaches and fleas to mosquitoes," says Michael F. Potter, PhD. He is an entomologist at the University of Kentucky in Lexington. "Never have they proven themselves to be effective control tools. If anything, I would expect the bugs to utilize them as a [haven], since they often emit small amounts of heat, which serves as a short-range attractant to bedbugs."

According to Potter, "the results are not surprising, but useful in the sense that they debunk another so-called secret weapon in the battle against bedbugs. As is often the case in pest control and life in general, if something sounds too good to be true, it probably is."

Susan C. Jones, PhD, agrees. She is an associate professor of entomology at Ohio State University in Columbus. "They are popular for all sorts of insects and rodents," she says. But "the research does not support the claims that the manufacturer makes. They typically don't work."

Prevent Bedbug Infestations

These devices retail for $20 to $40. "I would take that money and use it to launder all clothes and put them in a sealed tote, because this would protect them more than [ultrasonic] detection," Jones says.

Drying bedding and clothing at high temperatures for 20 minutes kills bedbugs, she says.

What else can you do?

"Bedbugs are a labor-intensive and time-intensive insect to deal with," Jones says. If you suspect you have bedbugs, call a professional and they can tell you if it is a look-alike or a real bedbug.

Dini Miller, PhD, is an associate professor of urban entomology at Virginia Tech in Blacksburg, Va. "If these worked, we wouldn't have a bedbug problem in the U.S.," she says.

Unfortunately, "we don't have a great answer for bedbugs right now," she says. "We are pretty good at taking care of 12 bedbugs, but where things get tough is when you have 1,200."

Heat and insecticides are the best available answers now, but they are not fail-safe.

The best way not to get a bedbug infestation is to keep the critters out of your home.

"It doesn't matter if you notice a few when travelling or get bites," Miller says. "You just don't want them to come home with you." Check yourself and any belongings before you come home.